The Vilter Single Screw compressor is a rotary, positive displacement compressor which incorporates a main screw and two gaterotors. Compression of the gas is accomplished by the engagement of the two gaterotors with the helical grooves in the main screw. The drive shaft imparts rotary motion to the main screw which in turn drives the intermeshed gaterotors.

The compressor is comprised of three fundamental components that rotate and complete the work of the compression process. This typically includes a cylindrical main screw with six helical grooves and two planar gaterotors, each with 11 teeth. The rotational axes of the gaterotors are parallel to each other and mutually perpendicular to the axis of the main screw.